Some questions on energy of orbitals

Ezio3.1415

1. We know px,py,pz are degenerate orbitals... My question is suppose in
0=[He] 2s^2 2px^2 2py^1 2pz^1
Are the px,py,pz orbitals degenerate here?

2. What is the reason of inert pair effect?

3. What is the order of shielding effect for s,p,d,f?

Ezio3.1415

Oh... no one answered... Okay can anyone only answer 1 & 3...